Coke and gas manufacture



IN VEN TOR.

Sept. 18, 1934. G. J NORDMEYER COKE AND GAS MANUFACTURE Filed Sept. 24.1931 2 Sheets-Sheet l Gera/aJ/Yardmg r.

' AIT N P G. J. NORDMEYER 1,973,909

COKE AND GAS MANUFACTURE Filed Sept. 24. 1931 2 Sheets-Sheet 2 rawmenial: era/od/Vora mger Patented Sept. 18, 1934 UNITED STATES PATENT:OFFICE 1,973,909 COKE AND GAS MANUFACTURE Gerald J. Nordmeyer, Nutley,N. J., assignor to The Koppel-s Company of Delaware, a corporation ofDelaware 1 Application September 24,1931, Serial No. 564,799

4 Claims.

My invention relates to the operation of coke ovens. It relatesespecially to the manufacture of gas from oils, such.as heavy petroleumoils, in coke ovens.

5 Batteries of by-product coke ovens are generally operated primarilyfor the production of two products-coke and gas. The market for theseproducts usually varies with the seasons, and the relative demand forcoke and gas is also subject to seasonal fluctuation. Coke producedduring the slack season is readily stored until there is a better marketfor it, but gas must generally be produced at a rate substantially'corresponding to the current demand.

Flexibility with regard to the amount of gas produced is therefore ahighly desirable feature of coke oven installations, and various meansof' achieving this flexibility have been devised. For example, duringthe season when the demand for gas is small, part of the gas produced bythe battery may be employed for underfiring, and when the demandincreases, producer gas or water gas is employed for underfiring,releasing all of the coke-oven gas for sale. The supply of surplus gascan be further augmented by manufacturing water gas from the cokeproduced.

Such expedients require considerable equipment in addition to thecoke-oven battery, in the form of gas producers or water-gas sets, andsince this equipment is not usually in continuous operation itsmaintenance and occasional operation add appreciably to the cost of thegas produced.

To eliminate this expense and to increase the flexibility of thecoke-oven operation, various attempts have been made in the past toemploy coke ovens for carbonizing hydrocarbon oils such as pitch andcertain petroleum fractions capable of producing large quantities of gasper unit of space required.

The gasification or distillation of heavy hydrocarbon oils, such as theso-called bunker oil, in coke ovens, has been rather carefully studied.It has been found that a typical coke oven, such as one of the typedescribed in the Becker Patent No. 1,374,546, with a coking capacity oftons of coal per day, can convert 5,000 gallons of bunker oil or thelike into gas and coke per day.

Each ton of coal produces about 11,000 cubic feet of 550 B. t. u. gas,and when coal gas is employed for underfiring, about 40% of this amountis required, leaving 6,600 cubic feet of surplus gas per ton of coal.The equivalent amount of oil, 250 gallons, produces about 20,000 cubicfeet of 1250 B. t. u. gas, and if this is diluted to 500 B. t. u. percubic foot, the gas production is 44,500 cubic feet.

This makes the ratio of maximum to minimum gas production about 7 to 1,and the amount of gas produced by a battery of coke ovens can be variedas desired within this ratio by gasifying oil in part of the ovens, andcoal in the others.

Since the amount of gas produced by any given battery of coke ovens canbe varied over a range which is greater than the usual differencebetween the minimum daily load and the maximum daily load on a gas plantor gas distributing system, it seems that gasification of oil incoke-oven batteries should be a solution of the'problem of providingsuflicient flexibility for gas plant purposes. However, technicaldifficulties have been I encountered which have in the past preventedthe general adoption of this practice. For example, it has beendiflicult to obtain a good grade of coke, tar production has been high,and the yield and. quality of oil gas have frequently fallen below theresults theoretically obtainable, and actually obtainable under optimumconditions.

An object of my present invention is to provide a method of gasifyingheavy hydrocarbon oils, such as bunker oil, in by product coke ovens,whereby the difficulties previously encountered in converting such oilsinto coke and gas are overcome.

A second object of my inventionis to provide 35 a method of operatingcoke ovens which is more flexible with respect to the quantity of gasproduced than methods previously employed.

Another object of my invention is to provide an improved method ofproducing oil gas in coke ovens, and suitable apparatus therefor.

My invention has for further objects such other operative advantages andresults as are found to obtain in the process and apparatus describedand claimed herewith.

The nature of my invention is such that existing coke-oven installationsof any usual type, such as the Becker oven described in the patentreferred to hereinabove, for example, can readily be adapted to itspractice. My invention contemplates introducing oil into the lowerportion of a coking chamber by means ,of oil spray lines or the like,which may be inserted through the charging holes in the oven top. Thesesprays and pipes are preferably fabricated from temperature-resistantmetal, and extend about half or two thirds of the distance from the topto the bottom of the oven. They may terminate about three to five feetfrom the bottom of the oven, for example.

By this means, coking or carbonization of the oil residue is caused totake place chiefly in the lower part of the oven chamber, and the-freespace in the upper part of the oven allows fixing of the oil gas beforeits discharge from the coking chamber. The yield and quality of the gasmay be further improved if an atmosphere of steam or blue water gas ismaintained in the oven, as the oil gas is thus fixed more effectively.

I will now describe the details of my invention with reference to theaccompanying drawings, in which Figure 1 is a vertical sectional view ofa coke oven adapted to the practice of my improved method of coke-ovenoperation and oil gasification.

Fig. 2 is a vertical sectional view transversely of Figure 1.

A coke-oven battery consists of any desired number of ovens, such astheoven generally indicated bythe numeral 2 in the drawing. Each oven isprovided with a suitable number of charging ports or openings 3, threeof which are shown in the present instance. The ovens are heated to thedesired temperature in a known manner by suitably arranged flues in thewalls surrounding the coking chamber.

An offtake 5 and ascension pipe 6 conduct gases from each oven to acollecting main 7. In some instances when coal is coked in part of theovens of a battery and oil in others, and under other circumstances, itmay be preferable to employ two collecting mains, which may both beconnected to the ascension pipes 6, or which may be at opposite ends ofthe ovens, each of which is then provided with two ascension pipes.Removable doors 9 and 10 are provided at the ends of each oven.

Each of the branch pipes 12 is connected with a series of pipes 14,which are usually smaller than the pipes 12, and which correspond innumber to the number of ovens in which oil is to be coked. Thesepipes'14 extend through discs or other suitable closing means 15 in thecharging ports 3 of the ovens to which oil is delivered.

Each pipe 14 contains a valve 1'7 or other suitable means forcontrolling the flow of oil therethrough, and each terminates in a spraynozzle 18, or other suitable distributing means, which is preferablyabout three to five feet from the bottom or sole of the oven, aspreviously stated. Oil is delivered into the heated oven eithercontinuously or intermittently at a rate corresponding to the size ofthe oven and the temperature maintained therein. In an oven of the usualsize, this rate might'be about 25 gallons per minute when thetemperature of the oven is about 1450 to 1500 F.

The oil is heated before its discharge from the sprays 18 by passingthrough pipes 14. It may also be preheated to any desired extent bymeans of steam coils in the oilstorage tank, or by circulating itthrough the flushing main or collecting main '7 before delivering it tothe pipes 12, in the manner described in the copending application of C.J. Ramsburg, Serial No. 555,228, filed August 5, 1931.

Whether the oil is supplied continuously at a rate corresponding to therate at which the residue is coked, or intermittently at a higher ratewith the flow periodically interrupted to allow volatile material tovaporize and the residue to carbonize, oil coke is formed and builds upin the bottom of the oven chamber, and oil vapor and gas are given offin large quantities.

When the deposit of coke has reached a sumcient depth, such as a depthapproximating but preferably somewhat. lessthan the distance between thesprays 18 and the bottom of the oven,.

the supply of oil is temporarily discontinued, and the coke is pushedout in the usual manner through the doors 9 and 10.

The oil gas and vapor is cracked or fixed in the free space above thesprays 18 in the oven chamber, from which it then passes through theascension pipe 6 to the collecting main 7. This provision of a crackingor fixing space or chamber within the coke oven and out of contact withthe oil spray greatly improves the quality of gas evolved, anddelivering the oil to the lower part of the oven makes this possible andsubstantially limits coke formation to the lower part of the oven.

Still more favorable results are obtained if an atmosphere of steamand/or blue water gas is maintained in the parts of theoven chamber.where most of the cracking occurs. I have found that this may be readilyaccomplished by injecting steam into the lower part of the oven, asthrough passages 21 which may terminate in sprays or nozzles 22.

These nozzles may conveniently be mounted on the coke-oven doors 9 and10, respectively, through which the passages 21 penetrate, as shown.They are supplied with steam from steam pipes 24 and 25, to which theyare connected by flexible hoses 26, and readily detachable couplingmembers 27. The flow of steam through these nozzles is controlled byvalves 28 or other suitable means. The passages 21 are preferablyinclined downwardly so that steam is discharged toward the bottom of thechamber, where coke is first deposited.

As n alternative, steam may be supplied to the cham r through a suitableduct and ports opening upward into the chamber. In either case, thesteam reacts with coke deposited in the lower part of the oven to formblue water gas, thereby increasing the yield of gas and improving itsquality, as well as reducing the amount of coke formed and making itunnecessary to push coke as frequently.

The steam is preferably admitted at such a rate that it is substantiallycompletely decomposed before passing from the oven, at least in thelater stages of the operation.

It will be obvious to those skilled in the art that certainmodifications are possible in the process, apparatus, and materialsdescribed hereinabove without departing from the spirit of my invention,and it is my intention to cover in the claims such modifications as areincluded within the scope thereof.

I claim as my invention:

1. The method of manufacturing coke and gas from oil in a retort ovencomprising, introducing oil through pipes extending to a short distanceabove the bottom of the retort and spraying the oil on the bottomthereof while the retort is being heated and gradually accumulating theoil in a eaaeoe pile only part way up the retort and simul taneouslycoking it on said bottom, maintain ing an upper gas-fixing space freefrom entering oil and above the accumulating pile of oil in the lowerpart of the retort, externally heating the side portions of both thecoking oil pile and the upper gas-fixing space in the retort tosuperheat the major portion of the gas-fixing space which is opposite toand externally heated by said heating and thereby eifecting the cokingof the so introduced oil in the lower part of the retort andsuperheating. the upper gas fixing space in the retort, withdrawing oilgas thereby vaporized and distilled oil? from the retort through saidgas-fix ing gas space while it is superheated as afore said and freefrom entering oil and accumulated coking oil and thereby fixing said oilgas as it flows oif from the retort through said gas-fixing space, andwithdrawing finished coke from the retort.

2. A method as claimed in claim 1, and which includes the steps ofintroducing steam into the ccked oil to produce water gas therefrom andwithdrawing the water gas off through the retort simultaneously with thevaporized and distilled oil gas withdrawn as aforesaid.

. 3. A method as claimed in claim 1, and which includes the step ofintroducing steam intosaid retort to produce an atmosphere'of steam inthe gas-fixing gas-space to favor the fixing of the oil gas therein.

4. A method as claimed in claim 1, and which includes the steps ofintroducing steam into the coked oil to produce water gas and at a ratecorresponding to the rate at which the'steam is decomposed by reactionwith the coke produced as aforesaid, andwith'drawing the water gas soproduced off through the retort simultaneously with vaporizedganddistilled oil gas withdrawn as aforesaid. i

GERALD J NORDMEYER.

